There’s something about a simple chocolate sheet cake that feels like a warm hug on a busy day. I remember one afternoon when I decided to bake this cake on a whim—mostly because I was craving chocolate but didn’t want to fuss with anything complicated. The kitchen was a little chaotic; I had music playing too loud and a phone call I was trying to ignore. Somehow, amidst all that, the rich cocoa aroma started filling the air, and it immediately calmed my nerves. The batter was surprisingly thin, almost like a chocolatey whisper waiting to transform into something indulgent. Once it was out of the oven, the cake was so moist that I almost regretted cutting into it so soon—but the frosting made it impossible to resist. It wasn’t perfect, I spread the frosting a bit unevenly, but that’s the beauty of this cake: it’s forgiving and just plain delicious.
Why You’ll Love It:
- It’s quick to make, which means less time in the kitchen and more time enjoying the cake.
- The texture is wonderfully moist and tender, but the thin batter can be a bit tricky to pour without spilling if you’re not careful.
- This cake is baked in one pan, making cleanup easier—though I usually end up with frosting on my fingers anyway.
- The frosting is rich and creamy but not overly sweet, balancing the chocolate flavor nicely.
- It’s simple—and that’s kind of the point. No fancy techniques required, just good old-fashioned comfort.
If you’re worried about the frosting spreading evenly, don’t be. A spatula or even the back of a spoon works fine, and the cake’s charm comes through regardless.
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Classic Chocolate Sheet Cake Squares
- Total Time: 45 minutes
- Yield: 24 squares 1x
Description
A rich and moist chocolate sheet cake baked in a single pan and cut into perfect squares. This easy-to-make dessert is perfect for parties, gatherings, or an everyday sweet treat.
Ingredients
2 cups all-purpose flour
2 cups granulated sugar
3/4 cup unsweetened cocoa powder
2 teaspoons baking powder
1 1/2 teaspoons baking soda
1 teaspoon salt
1 cup buttermilk, room temperature
1/2 cup vegetable oil
2 large eggs, room temperature
2 teaspoons vanilla extract
1 cup boiling water
1/2 cup unsalted butter, softened
3 cups powdered sugar
1/3 cup unsweetened cocoa powder
1/3 cup milk
1 teaspoon vanilla extract
Instructions
Preheat the oven to 350°F (175°C). Grease and flour a 9×13-inch baking pan.
In a large mixing bowl, sift together the flour, granulated sugar, 3/4 cup cocoa powder, baking powder, baking soda, and salt.
In a separate bowl, whisk together the buttermilk, vegetable oil, eggs, and 2 teaspoons vanilla extract until well combined.
Add the wet ingredients to the dry ingredients and mix until smooth.
Carefully stir in the boiling water until the batter is thin and well combined.
Pour the batter evenly into the prepared baking pan.
Bake for 30 minutes or until a toothpick inserted into the center comes out clean.
Remove the cake from the oven and allow it to cool completely in the pan on a wire rack.
While the cake cools, prepare the frosting by creaming the softened butter in a medium bowl until smooth.
Gradually add the powdered sugar and 1/3 cup cocoa powder, alternating with the milk, beating until the frosting is smooth and spreadable.
Stir in 1 teaspoon vanilla extract.
Once the cake is completely cooled, spread the frosting evenly over the top.
Cut the cake into 24 squares and serve.
- Prep Time: 15 minutes
- Cook Time: 30 minutes
Kitchen Notes: I usually use a standard 9×13 pan for this recipe, nothing fancy, and it turns out great every time. Serving it with a cold glass of milk or a scoop of vanilla ice cream really elevates the experience. If you want to switch things up a bit, you could try adding a pinch of cinnamon to the batter or stirring in some chopped nuts for a little crunch. Sometimes I’ve wondered if swapping the buttermilk for sour cream would make it even moister, but I haven’t tested that enough yet to say for sure. Also, if you’re feeling adventurous, a drizzle of caramel sauce over the frosted cake squares is surprisingly good.
FAQ:
Can I make this cake ahead of time?
Yes, you can bake the cake a day in advance and frost it just before serving to keep it fresh.
How should I store leftover cake?
Store leftovers in an airtight container at room temperature for a couple of days, or refrigerate if you want it to last a bit longer.
Is it possible to freeze this cake?
You can freeze the unfrosted cake for up to three months; just thaw completely before frosting.
This classic chocolate sheet cake squares recipe is the kind of dessert that fits perfectly into busy afternoons or casual get-togethers. Give it a try—you might find it becomes one of your quick chocolate fixes, too.